Cisco Adaptive Security Appliance Software
CVE-2019-15256
A vulnerability in the Internet Key Exchange version 1 (IKEv1) feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to improper management of system memory. An attacker could exploit this vulnerability by sending malicious IKEv1 traffic to an affected device. The attacker does not need valid credentials to authenticate the VPN session, nor does the attacker's source address need to match a peer statement in the crypto map applied to the ingress interface of the affected device. An exploit could allow the attacker to exhaust system memory resources, leading to a reload of an affected device.
What this means for your business
- It affects Cisco Adaptive Security Appliance Software. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 2% chance of attack attempts being seen in the next 30 days, ranking above 79% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Adaptive Security Appliance Software, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.6 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H- Weakness
- CWE-399
- Assigned by
- psirt@cisco.com
Dates
- Published
- 2019-10-02
- Last modified
- 2026-08-11
- Sources
- NVD
Affected products
- Cisco Adaptive Security Appliance Software9.7 - 9.8.4.10, 9.9 - 9.9.2.47, 9.10 - 9.10.1.30, 9.12 - 9.12.2.5
- Cisco Secure Firewall Threat Defense6.2.0 - 6.2.3.11, 6.3.0 - 6.3.0.2
- Cisco Asa 5505 Firmware9.9\(2.4\), 201.4\(1.21\)
- Cisco Asa 5505all versions
- Cisco Asa 5510 Firmware9.9\(2.4\), 201.4\(1.21\)
- Cisco Asa 5510all versions
- Cisco Asa 5512-X Firmware9.9\(2.4\), 201.4\(1.21\)
- Cisco Asa 5512-Xall versions
- Cisco Asa 5515-X Firmware9.9\(2.4\), 201.4\(1.21\)
- Cisco Asa 5515-Xall versions
- Cisco Asa 5520 Firmware9.9\(2.4\), 201.4\(1.21\)
- Cisco Asa 5520all versions
As listed in the NVD configuration data. Not a statement about your estate.